For Potia, a native of India, the delays mean she must keep leaving and reentering the US to maintain her temporary work visa, or forfeit her right to travel outside the country. Last spring, Potia spent $1,000 to travel from Cambridge, Mass., to Montreal – just to get her passport stamped. "What if I needed to go [home to India] for an emergency?" she asks. "I needed that stamp."

Immigration has been a hot topic of late. But amid the furor over illegal immigrants, the plight of legal migrants caught in a system that is slow, erratic, and often unresponsive is largely ignored.

The result: talented, hardworking people who play by the rules are trapped in limbo, and even close relatives of American citizens may wait up to a decade to enter the US.

"Ten years is half of a lifetime for a child," says Cristina Rodriguez, a law professor specializing in immigration at New York University. "The backlogs are keeping families apart and diminishing confidence in the system."

This month, President Bush moved to ease the backlog of green-card applications by allowing applicants to obtain permanent residency before FBI security checks are complete, a rule change that will almost instantly benefit 47,000 people.

More than 3 million people were waiting for green cards in 2006. More recent statistics are not available but experts suggest this backlog is unlikely to have reduced been dramatically since then, especially after the surge of applications last summer when an application fee hike – from $395 to $1,010 per person – prompted a record 300,000 people to apply in the months leading up to the increase.

By any standard, applying for US permanent residency – often a first step to citizenship – is an arduous, unpredictable process. Green-card applicants must find suitable sponsors, decipher complex legal jargon – for many, in an unfamiliar language – or spend thousands of dollars on lawyers to do it for them. They must gather and submit hundreds of pages of personal documents that vouch for their identity, professional qualifications, familial relationships, and financial security. They must also pay fees and expenses – for photos, medical examinations, and vaccinations – running into thousands of dollars.

And that's just to submit the application. Applicants can then spend years navigating bureaucracy – or just waiting. "When the system works, it works ... when it goes wrong, it's hard to fix it," said Patrick Klauss, a partner in the immigration law firm Berd & Klauss, PLLC, in New York City.

A nightmare for families

All prospective immigrants take the same first step toward getting their green cards: finding someone – an employer or a close family member – to sponsor their applications. Some avenues are easier than others: marrying a US citizen, for example, almost certainly ensures a green card within a year.

But no option is free of anxiety, and the potential for setbacks is endless.

Justin Fertitta, a young chef in New York City, was born in the United States and his wife, Chrissie, is from Malaysia and first came to the US on a student visa. The Fertittas applied for her green card shortly after their June 2006 wedding, but neglected to disclose that Mrs. Fertitta had been arrested for shoplifting as a teenager. "She stole a belt from J.C. Penney when she was 19," says Mr. Fertitta. "She didn't think it was an actual arrest, but it went down on paperwork."

Immigration officials brought up the arrest in the interview, accused the Fertittas of lying, and denied the green card. The couple applied again and were denied again. Their case went to immigration appeals court, to determine whether the couple get to stay together in the US.

"[I]t's a horrible system," says Fertitta. "It's the uncertainty and having other people mess with your life that's the worst."

Quotas haven't kept up with demand

Employers sponsoring green-card applicants must first prove that no American citizen can fill the job, then demonstrate that applicants are specially qualified for the position and that the company can pay them.

Some employers bend the rules – often at the applicant's expense. Sandra Braganza obtained her green card through her employer, the now-defunct Sheena Perfumes, which recruited her from India. The company made Ms. Braganza seem highly qualified, though she was not, by misrepresenting her salary. "So I took a 'paper' salary of $70,000, and I paid taxes on that money each year," says Ms. Braganza. Meanwhile, she struggled to survive in New York City on $25,000 a year.

Employment-based green cards are regulated by a quota system, which limits the cards issued each year. In countries like India, China, and Mexico, where quotas have not kept up with demand, the backlog stretches back years. State Department statistics show that some applications from those countries filed in 2001 are just now being processed.

It's this backlog that delayed the early stages of Potia's green card.

By contrast, those sponsored by a family member – either a permanent resident or a US citizen – undergo a relatively simpler process. They must prove the familial relationship and their sponsor must show they can support the applicant with an income at 125 percent of the federal poverty line. A family of four, for instance, must earn at least $26,500 a year

Family-sponsored applications are also subject to a quota system, except for immediate relatives of US citizens – parents, children, or spouses.

Again, demand from certain countries including India, China, and Mexico far exceeds availability, and the process can take years.

An estimated 4 million people outside the US are waiting for visas to become available, says Saucier.

He attributes the delays to inefficiency in its processing systems. The agency started a backlog elimination program in 2003, he says, after it split off from the Department of Justice and shed border patrol and other enforcement duties. By the end of 2006, Saucier claims, much of the backlog had been eliminated and processing times for "high preference" applications and those not subject to quotas had improved measurably.

Extended post-9/11 FBI security checks have delayed some green card applications – about 1 percent, or nearly 4,000 each year – by a year or more due, says Saucier, to the FBI's inefficient, paper-based systems, which don't jibe with his department's electronic systems.

It's not over till it's over

In the final stage of the process, applicants are interviewed by immigration officials. Those sponsored by a spouse often have the most challenging interviews. Because marriage-based green-card applications have the highest rate of fraud, couples must prove they married in "good faith," with documentation such as jointly held leases and mortgages, bank accounts, and insurance. Officials question couples closely.

"The agent was asking my wife questions, doubting her motives for the wedding, and I don't think she took that well," says Gustavo Vicentini, a Boston-based consultant from Brazil who was sponsored by his wife, Allison, a US citizen by birth. But, he adds, "They have to be careful. They are going to start from the presumption that we are here with bad intentions."

For the Fertittas, there is a happy ending. At their final court hearing on Feb. 15, the judge approved Mrs. Fertitta's green card, ruling that the shoplifting offense was too minor a reason to keep a couple apart. "It's a weight off," says Fertitta. "Now we can plan trips, we can go back to Malaysia and get to see where she grew up."

Potia, however, is still not sure how much longer she will have to wait. "It all depends on ... where you're at in the system," she said. "You just don't know."